This invention relates generally to seals and more particularly to a seal for a rotary collection core of a disc filter or the like. In the prior art, the collection channels, within the rotating core pipe, conduct liquid filtrate from submerged sectors of the disc filter and bypass air from the emerged sectors to a separation valve plate. Typically, the separation valve plate is a disc like structure having arcuate cutouts which permit the collected filtrate to drain either to an atmospheric drain or a vacuum drain. Vacuum is typically produced by barometric drop legs exiting a vacuum box in which the separation valve is placed.
Typically, the core to vacuum box seal is accomplished by a so-called deckle ring seal between a flange ring on the vacuum box and a seal ring on the core. Since both surfaces of the seal are circumferential, the deckle ring type seal normally does an adequate job of sealing the rotating core to the stationary vacuum box. The sealing surface between the core and the valve plate, however, are end to face which is sensitive to wear and axial movement during rotation. Excessive gaps between the end of the core and the valve plate permits substantial quantities of air to be drawn into the vacuum box thereby reducing the vacuum efficiency created by the barometric legs.
The foregoing illustrates limitations known to exist in present devices and methods. Thus, it is apparent that it would be advantageous to provide an alternative directed to overcoming one or more of the limitations set forth above. Accordingly, a suitable alternative is provided including features more fully disclosed hereinafter.